[Drsagacity]

Which headers did you add. Did you happen to dyno before and after to see the impact of headers on a FI car? It makes sense they would help, but watching cars run 700rwhp with stock internals and exhaust makes me wonder how important it is.

What do you think?

[Atomic Ed]

I focused on the intake side of the equation on my Edelbrock. Rotofab, ported throttle body, ported snout, and down one size from the stock upper pulley. About $600 dollars outlay, and with a little work, walked away with a extra 100 rwhp and torque. Much better bang for the buck.

662 rwhp on the stock exhaust and still lots of potential left. Definitely would benefit from a set of headers, but I'm out of the safe zone of the pistons. Headers would just push me that farther off the cliff.

Besides, It still sounds stock. I like the stealth approach.

[Drsagacity]

Really great feedback. Kind of what I was thinking too. Although headers will lower boost too, right? In some ways I wonder if freeing up the exhaust might make it safer. I have added headers on my other builds, but other than sound, I always coupled it with too many other changes to really assign a value.

[Atomic Ed]

It will lower your boost, but mass airflow will increase. By the time you tune for the increased flow, your risk factor will be about the same....might be a little lower risk, but not much.

[Drsagacity]

Originally Posted by Atomic Ed

It will lower your boost, but mass airflow will increase. By the time you tune for the increased flow, your risk factor will be about the same....might be a little lower risk, but not much.

Did you have to address fuel to reach that level? We saw the hpfp dropping above 550rwhp so we dialed it back to 550rwhp to be safe.

Those are really solid numbers on the Edelbrock...nice. That’s a blower I have never seen in person.

The headers definitely make the car louder. I am planning to go with the JRE cam...I think I am leaning toward forged pistons instead of headers...but hoping someone on the forum has some insight to share.

[Atomic Ed]

The Edelbrock and the Magnuson are basically twin sisters. Very comparable overall.

As for the fuel, I did add a ZL1 pump in the tank and we tweaked both the ZL1 pump and the stock HPFP control modules to get the fuel we needed.

[Drsagacity]

Originally Posted by Atomic Ed

The Edelbrock and the Magnuson are basically twin sisters. Very comparable overall.

As for the fuel, I did add a ZL1 pump in the tank and we tweaked both the ZL1 pump and the stock HPFP control modules to get the fuel we needed.

I have fuel components sitting in my office now, waiting for install so I can up the boost. I am also going to add e85 for a little more.

Back to regularly scheduled programming, I am curious if anyone is seeing a big benefit from headers with the FI application. At what power level do we need them?

[Dysan911]

After I did my fuel mods and went to a smaller pulley on my P1. During the tuning phase we were trying to chase down some knock retard occurring up high during every pull. Ted Jannetty who tunes my car suggested it was probably time I consider LT's with either highflow cats or an off road pipe to resolve this issue. I believe he ran into the same problem with the Hellion Twin Turbo setup as well. It's my assumption that once the stock cats are removed or replaced with a high-flow version will lower the boost and allow you to run better timing and make more power.

Also isn't it pretty common that FI vehicles run the risk of melting stock cats?

Really old post but if you google the topic it's pretty common

https://www.camaro5.com/forums/showthread.php?t=183230

[Drsagacity]

Originally Posted by Dysan911

After I did my fuel mods and went to a smaller pulley on my P1. During the tuning phase we were trying to chase down some knock retard occurring up high during every pull. Ted Jannetty who tunes my car suggested it was probably time I consider LT's with either highflow cats or an off road pipe to resolve this issue. I believe he ran into the same problem with the Hellion Twin Turbo setup as well. It's my assumption that once the stock cats are removed or replaced with a high-flow version will lower the boost and allow you to run better timing and make more power.

Also isn't it pretty common that FI vehicles run the risk of melting stock cats?

Really old post but if you google the topic it's pretty common

https://www.camaro5.com/forums/showthread.php?t=183230

Yeah. Let headers and high flow cats seem to be the way. I suppose I will need to add that along with the cam and pistons. Now to find a brand and an option to work with the convertibles.

After the high flow cats and headers did the tuning problem disappear? Which headers did you go with?

[Joe's_cool_1le]

Originally Posted by Dysan911

After I did my fuel mods and went to a smaller pulley on my P1. During the tuning phase we were trying to chase down some knock retard occurring up high during every pull. Ted Jannetty who tunes my car suggested it was probably time I consider LT's with either highflow cats or an off road pipe to resolve this issue. I believe he ran into the same problem with the Hellion Twin Turbo setup as well. It's my assumption that once the stock cats are removed or replaced with a high-flow version will lower the boost and allow you to run better timing and make more power.

Also isn't it pretty common that FI vehicles run the risk of melting stock cats?

Really old post but if you google the topic it's pretty common

https://www.camaro5.com/forums/showthread.php?t=183230

I trashed my high flow cats on my 1 7/8 Kooks in less then 6 months. That was during the hot season with excess beating.

[Dysan911]

Originally Posted by Drsagacity

After the high flow cats and headers did the tuning problem disappear? Which headers did you go with?

Haven't gotten them yet but plan on running a set of 1 7/8 American Racing Headers in the very near future with HF Cats. Ted was able to resolve the KR but I'm pretty certain we left some power on the table due to the timing, etc that was pulled out.

[Dysan911]

Originally Posted by Joe's_cool_1le

I trashed my high flow cats on my 1 7/8 Kooks in less then 6 months. That was during the hot season with excess beating.

Oh wow. I was hoping to hear the HF version were built to withstand more abuse. I considered running no cats but would prefer to have them to help control the exhaust volume/rasp and prevent the fuel smell.

[Mark114]

Originally Posted by Dysan911

Also isn't it pretty common that FI vehicles run the risk of melting stock cats?

Actually I think it might be the other way around. I believe the factory cats are ceramic and can take the heat but maybe don't have the flow. Aftermarket cats are coiled metal foil that can soften and deform under high pressure IIRC.

[Drsagacity]

Geesh. This is bringing back bad memories of one of the adventures I had with a Vette.

The combination cam, LT headers and no cats = too loud and momma didn’t even want to drive in the car.